Hi Ramona, thanks for reaching out!
It sounds like the form you filled out was created using a work or school account, and it’s set to block access from personal Microsoft accounts. That’s why you’re getting the sign-in error.
To fix this, you’ll need to contact the person or organization who shared the form and ask them to either change the access settings or send you a copy of your response. Microsoft Forms only allows personal accounts if the form owner has enabled that option.
Warm Regards,
Arlene D.